Coenzyme Q10, also referred to herein as CoQ10, ubiquinone, or ubidecarenone, is a popular nutritional supplement and can be found in capsule form in nutritional stores, health food stores, pharmacies, and the like, as a vitamin-like supplement to help protect the immune system through the antioxidant properties of ubiquinol, the reduced form of CoQ10. CoQ10 is found throughout most tissues of the human body and the tissues of other mammals. CoQ10 is very lipophilic and, for the most part, insoluble in water. The insolubility is related to the 50-carbon atom isoprenoid side chain, of hydrocarbon nature as shown in the following structure of CoQ10.

Coenzyme Q10 (CoQ10) is an integral component of the oxidative phosphorylation machinery in mitochondria and is implicated in homeostasis of biological membranes and cellular redox status. The reduced form of CoQ10 (CoQ10H2) is involved in many key physiochemical functions, including serving as an antioxidant, production of ATP, and intercalation with membrane lipids to maintain structure.